Conventional greenhouses are normally made up of metal frameworks on which vinyl sheets joined together by means of rubber or plastic belts are mounted.
A problem common to all these greenhouses is the rusting of the metal framework, which leads to significant deterioration of the structure and its support conditions with time and its eventual collapse.
Modular structures have been designed made up of side members consisting of half-round rods and horizontal cross members, which are attached at their intersection points to form a framework that is covered with a laminar plastic casing that constitutes the shell of the greenhouse. In this case the side members and cross members are made of metallic material, which means that the framework is subject to the deterioration caused by the rusting of these elements.
There are greenhouses intended for growing flowers in their interior, consisting of aluminium tubes and glass, which are more resistant to corrosion, although they certainly prove expensive.
Structures of this type, conventionally used to maintain environmental conditions, particularly when it comes to sheltering the crops housed inside from the cold, require the provision of a suitable system of framework insulation and sealing. It is a question of preventing the thermal differences that are detrimental to the crops, especially sharp changes between night and daytime temperatures.
Some of the structures designed for use as greenhouses also take the form of awnings that are used for performing such different functions as forming an enclosure for a heated swimming-pool or a garage for vehicles.
The problems that affect greenhouses also apply to awnings of this type, but in any case they are amenable to solution by means of the invention described here.